#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
using namespace std;
void Swap(int& left, int& right)
{
    int temp = left;
    left = right;
    right = temp;
}

void Swap(double& left, double& right)
{
    double temp = left;
    left = right;
    right = temp;
}

void Swap(char& left, char& right)
{
    char temp = left;
    left = right;
    right = temp;
}
template<typename T>
void Swap(T& a, T& b)
{
    T c = a;
    a = b;
    b = c;
}
int main()
{
    double a = 1.0;
    double b = 2.0;
    Swap(a, b);
    cout << a << endl;
    return 0;
}